Using entire modern and ancient mitochondrial genomes of Adélie penguins (Pygoscelis adeliae) that are up to 44000 years old, we show that the rates of evolution of the mitochondrial genome are two to six times greater than those estimated from phylogenetic comparisons. Although the rate of evolution at constrained sites, including nonsynonymous positions and RNAs, varies more than twofold with time (between shallow and deep nodes), the rate of evolution at synonymous sites remains the same. The time-independent neutral evolutionary rates reported here would be useful for the study of recent evolutionary events.

10 comments:

I feel that there is a misunderstanding somewhere. "Greater" seems to mean slower, at least attending to the press release:

Penguins that died 44,000 years ago in Antarctica have provided extraordinary frozen DNA samples that challenge the accuracy of traditional genetic aging measurements, and suggest those approaches have been routinely underestimating the age of many specimens by 200 to 600 percent.

In other words, a biological specimen determined by traditional DNA testing to be 100,000 years old may actually be 200,000 to 600,000 years old, researchers suggest in a new report in Trends in Genetics, a professional journal.

Don't say that, mate. You'll get Dienekes ranting about the Germline theory of Mr Z, the goose with the has a disgustingly long surname.

You know what I mean, his belief that the ages of haplogroups are overestimated and should be divided by three. Of course it only applies to the so called Semitic haplogroup J1, the over estimation of the age of R1b to make it Paleolithic, and Cro Magnoid is set in Ice Age stone and cannot be similarly revised, or even recalculated.

We have much better methods in this century, than we had in the last century to estimate the ages of haplogroups.

Dienekes is consistent, AFAIK. He has defended that R1b in Europe is of Neolithic origin too.

In fact with the ultra-fast rates he and a few others have proposed, only Y-DNA I could be claimed (and not too safely) to be Paleolithic in Europe.

But, anyhow, the question is to get the matter clarified and stop the speculation as much as possible. Using fossil DNA is surely the only way to explain anything. Same as happened with the Neanderthal-Sapiens interbreeding controversy.

Scientists use the “molecular clock”—an estimated rate of DNA mutation—to date key events such as migrations and the divergence of species. But just how accurately the clock keeps time has long been debated. A new study of living and ancient Antarctic penguins, like those on Ross Island at left, suggests that DNA mutates six times faster than predicted. That could mean that some species—such as chimps and humans—could have split off from each other much more recently in time than previously thought. The finding should help improve the dating of relatively recent events, including when people domesticated various crops and animals, and when major human migrations occurred.

I see no evidence that R1b is significantly more diverse in West Asia than in Southeast Europe.

You could find such evidence in the various FTDNA geographic projects which contain R1b1b2 haplotypes. Looking only at the M269+ samples, you'd see that the "West Asian" projects (R-Arabia, Turkey, Assyrian, Armenian) have a ten marker variance (xDYS385) of 3.28: higher than the Greek project (2.44) or the Italy Project (2.68).

In fact none of the West Asian projects have a R1b1b2 variance lower than either Greek or Italy.

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